// Copyright (c) 2012 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#include "content/browser/renderer_host/pepper/pepper_gamepad_host.h"

#include "base/bind.h"
#include "content/public/browser/browser_ppapi_host.h"
#include "device/gamepad/gamepad_service.h"
#include "ppapi/c/pp_errors.h"
#include "ppapi/host/dispatch_host_message.h"
#include "ppapi/host/host_message_context.h"
#include "ppapi/host/ppapi_host.h"
#include "ppapi/proxy/ppapi_messages.h"
#include "ppapi/shared_impl/ppb_gamepad_shared.h"

namespace content {

PepperGamepadHost::PepperGamepadHost(BrowserPpapiHost* host,
    PP_Instance instance,
    PP_Resource resource)
    : ResourceHost(host->GetPpapiHost(), instance, resource)
    , browser_ppapi_host_(host)
    , gamepad_service_(device::GamepadService::GetInstance())
    , is_started_(false)
    , weak_factory_(this)
{
}

PepperGamepadHost::PepperGamepadHost(device::GamepadService* gamepad_service,
    BrowserPpapiHost* host,
    PP_Instance instance,
    PP_Resource resource)
    : ResourceHost(host->GetPpapiHost(), instance, resource)
    , browser_ppapi_host_(host)
    , gamepad_service_(gamepad_service)
    , is_started_(false)
    , weak_factory_(this)
{
}

PepperGamepadHost::~PepperGamepadHost()
{
    if (is_started_)
        gamepad_service_->RemoveConsumer(this);
}

int32_t PepperGamepadHost::OnResourceMessageReceived(
    const IPC::Message& msg,
    ppapi::host::HostMessageContext* context)
{
    PPAPI_BEGIN_MESSAGE_MAP(PepperGamepadHost, msg)
    PPAPI_DISPATCH_HOST_RESOURCE_CALL_0(PpapiHostMsg_Gamepad_RequestMemory,
        OnRequestMemory)
    PPAPI_END_MESSAGE_MAP()
    return PP_ERROR_FAILED;
}

int32_t PepperGamepadHost::OnRequestMemory(
    ppapi::host::HostMessageContext* context)
{
    if (is_started_)
        return PP_ERROR_FAILED;

    gamepad_service_->ConsumerBecameActive(this);
    is_started_ = true;

    // Don't send the shared memory back until the user has interacted with the
    // gamepad. This is to prevent fingerprinting and matches what the web
    // platform does.
    gamepad_service_->RegisterForUserGesture(
        base::Bind(&PepperGamepadHost::GotUserGesture,
            weak_factory_.GetWeakPtr(),
            context->MakeReplyMessageContext()));
    return PP_OK_COMPLETIONPENDING;
}

void PepperGamepadHost::GotUserGesture(
    const ppapi::host::ReplyMessageContext& context)
{
    base::SharedMemoryHandle handle = gamepad_service_->GetSharedMemoryHandleForProcess(
        browser_ppapi_host_->GetPluginProcess().Handle());

    context.params.AppendHandle(ppapi::proxy::SerializedHandle(
        handle, sizeof(ppapi::ContentGamepadHardwareBuffer)));
    host()->SendReply(context, PpapiPluginMsg_Gamepad_SendMemory());
}

} // namespace content
